I have not tried Methotrexrate, so can't comment on that. But I wanted to suggest you try the Plaquenil and Neurontin first before adding an additional medication. Otherwise you won't know what works, what doesn't, and if you get side-effects, which medication caused it.

The Plaquenil can take months to be effective. It takes a good 60 days just to build up in the system, then time to work. So don't hope for any immediate results...because it won't happen.

I'm assuming the Neurontin for PN from the Sjogren's?? If you symptoms are getting worse after stopping IVIG, I would reconsider the IVIG (possibly) if you don't have good results from the Neurontin. This also takes time to build up to a therapeutic dose...not months, but weeks at least to find a suitable dose that doesn't make you a zombie in the process...

I'm curious why JH dismissed the lab work for Sjogren's? It appears classic for Sjogren's. Can you explain their logic?